package com.mining.app.zxing.view;

import java.util.Collection;
import java.util.HashSet;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.support.v4.content.ContextCompat;
import android.util.AttributeSet;
import android.view.View;

import com.google.zxing.ResultPoint;
import com.mining.app.zxing.camera.IMECameraManager;
import qs.openxt.libs.R;

public final class IMEViewfinderView extends View {
	/**
	 * 刷新界面的时间
	 */
	private static final long ANIMATION_DELAY = 10L;
	private static final int OPAQUE = 0xFF;

	/**
	 * 四个绿色边角对应的长度
	 */
	private int ScreenRate;

	/**
	 * 四个绿色边角对应的宽度
	 */
	private static final int CORNER_WIDTH = 4;

	/**
	 * 中间那条线每次刷新移动的距离
	 */
	private static final int SPEEN_DISTANCE = 5;

	/**
	 * 手机的屏幕密度
	 */
	private static float density;
	/**
	 * 字体大小
	 */
	private static final int TEXT_SIZE = 16;
	/**
	 * 字体距离扫描框下面的距离
	 */
	private static final int TEXT_PADDING_TOP = 30;

	/**
	 * 画笔对象的引用
	 */
	private Paint paint;

	/**
	 * 中间滑动线的最顶端位置
	 */
	private int slideTop;

	/**
	 * 将扫描的二维码拍下来，这里没有这个功能，暂时不考虑
	 */
	private final int maskColor;

	private final int resultPointColor;
	private Collection<ResultPoint> possibleResultPoints;
	private Collection<ResultPoint> lastPossibleResultPoints;

	boolean isFirst;

	public IMEViewfinderView(Context context, AttributeSet attrs) {
		super(context, attrs);

		density = context.getResources().getDisplayMetrics().density;
		// 将像素转换成dp
		ScreenRate = (int) (20 * density);

		paint = new Paint();
		maskColor = ContextCompat.getColor(context, R.color.qrcode_viewfinder_mask);

		resultPointColor = ContextCompat.getColor(context, R.color.qrcode_possible_result_points);
		possibleResultPoints = new HashSet<ResultPoint>(5);
	}

	@Override
	public void onDraw(Canvas canvas) {
		// 中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改
		Rect frame = IMECameraManager.get().getFramingRect();
		if (frame == null) {
			return;
		}

		// 初始化中间线滑动的最上边和最下边
		if (!isFirst) {
			isFirst = true;
			slideTop = frame.top;
		}

		// 获取屏幕的宽和高
		int width = canvas.getWidth();
		int height = canvas.getHeight();

		paint.setColor(maskColor);

		// 画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面
		// 扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边
		canvas.drawRect(0, 0, width, frame.top, paint);
		canvas.drawRect(0, frame.top, frame.left, frame.bottom, paint);
		canvas.drawRect(frame.right, frame.top, width, frame.bottom, paint);
		canvas.drawRect(0, frame.bottom, width, height, paint);

		// 画扫描框边上的角，总共8个部分
		paint.setColor(ContextCompat.getColor(this.getContext(), R.color.label_color0));
		canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate,
				frame.top + CORNER_WIDTH, paint);
		canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH,
				frame.top + ScreenRate, paint);
		canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right,
				frame.top + CORNER_WIDTH, paint);
		canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right,
				frame.top + ScreenRate, paint);
		canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left
				+ ScreenRate, frame.bottom, paint);
		canvas.drawRect(frame.left, frame.bottom - ScreenRate, frame.left
				+ CORNER_WIDTH, frame.bottom, paint);
		canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH,
				frame.right, frame.bottom, paint);
		canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate,
				frame.right, frame.bottom, paint);

		// 绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE
		slideTop += SPEEN_DISTANCE;
		if (slideTop >= frame.bottom) {
			slideTop = frame.top;
		}

		Rect lineRect = new Rect(frame.left, slideTop, frame.right, slideTop + 11);
		canvas.drawBitmap(BitmapFactory.decodeResource(getResources(), R.mipmap.flicking_icon_scanningline), null, lineRect, paint);

		// 画扫描框下面的字
		paint.setColor(Color.WHITE);
		paint.setTextSize(TEXT_SIZE * density);
		paint.setAlpha(0x60);
		paint.setColor(Color.WHITE);
		String text = getResources().getString(R.string.qrcode_scan_text);
		float textWidth = paint.measureText(text);
		canvas.drawText(text, (width - textWidth) / 2, (float) (frame.bottom + (float) TEXT_PADDING_TOP * density), paint);

		Collection<ResultPoint> currentPossible = possibleResultPoints;
		Collection<ResultPoint> currentLast = lastPossibleResultPoints;
		if (currentPossible.isEmpty()) {
			lastPossibleResultPoints = null;
		} else {
			possibleResultPoints = new HashSet<ResultPoint>(5);
			lastPossibleResultPoints = currentPossible;
			paint.setAlpha(OPAQUE);
			paint.setColor(resultPointColor);
			for (ResultPoint point : currentPossible) {
				canvas.drawCircle(frame.left + point.getX(),
						frame.top + point.getY(), 6.0f, paint);
			}
		}
		if (currentLast != null) {
			paint.setAlpha(OPAQUE / 2);
			paint.setColor(resultPointColor);
			for (ResultPoint point : currentLast) {
				canvas.drawCircle(frame.left + point.getX(),
						frame.top + point.getY(), 3.0f, paint);
			}
		}

		// 只刷新扫描框的内容，其他地方不刷新
		postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top,
				frame.right, frame.bottom);

	}

	public void drawViewfinder() {
		invalidate();
	}

	/**
	 * Draw a bitmap with the result points highlighted instead of the live
	 * scanning display.
	 * 
	 * @param barcode
	 *            An image of the decoded barcode.
	 */
	public void drawResultBitmap(Bitmap barcode) {
		invalidate();
	}

	public void addPossibleResultPoint(ResultPoint point) {
		possibleResultPoints.add(point);
	}
}
